Construction of coral-like complex: Controlled growth of vaterite submicron hairs on flat films and hemispheres

The complexes of vaterite with the overall macromorphology of some type of coral were biomimetically constructed in the present study. The films and hemispheres of vaterite were obtained by the phase transformation of amorphous calcium carbonate on silicon wafer and mica, respectively. Subsequently, the growth of vaterite submicron hairs was induced on the vaterite substrates in the presence of poly (acrylic acid). It was found that poly (acrylic acid) and vaterite substrates were the key factors in the formation of submicron hairs of vaterite, which could be explained by the solution-precursor-solid (SPS) mechanism. Our work demonstrated an achievement of crystal morphogenesis of calcium carbonate by the controlled phase transformation and crystal growth.